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A157984 a(n) = n!/(7 * 20!). 0
3, 66, 1518, 36432, 910800, 23680800, 639381600, 17902684800, 519177859200, 15575335776000, 482835409056000, 15450733089792000, 509874191963136000, 17335722526746624000, 606750288436131840000, 21843010383700746240000 (list; graph; refs; listen; history; text; internal format)
OFFSET

21,1

COMMENTS

From calculations for a Witt design:

http://www.math.uic.edu/~ronan/Witt_design;

a(n)*8!/3! - 48*n!/19!

LINKS

Table of n, a(n) for n=21..36.

MATHEMATICA

Flatten[Table[If[IntegerQ[48*3!*n!/(8!*19! )], 48*3!*n!/( 8!*19! ), {}], {n, 0, 48}]] (* Roger L. Bagula *)

Select[With[{n=48 3!, d=8! 19!}, Table[(n  i!)/d, {i, 50}]], IntegerQ] (* Harvey P. Dale, Jan 05 2011 *)

f[n_] := n!/(7 * 20!); Array[f, 10, 21] (* Robert G. Wilson v, Jan 05 2011 *)

CROSSREFS

Sequence in context: A238471 A259457 A157543 * A187547 A157554 A185053

Adjacent sequences:  A157981 A157982 A157983 * A157985 A157986 A157987

KEYWORD

nonn

AUTHOR

Roger L. Bagula, Mar 10 2009

STATUS

approved

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Last modified August 12 09:17 EDT 2020. Contains 336438 sequences. (Running on oeis4.)